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Background: Indoor residual spraying (IRS) of insecticides is a key method to reduce vector transmission of Trypanosoma cruzi, causing Chagas disease in a large part of South America. However, the successes of IRS in the Gran Chaco region straddling Bolivia, Argentina, and Paraguay, have not equalled those in other Southern Cone countries. Aims: This study evaluated routine IRS practices and insecticide quality control in a typical endemic community in the Bolivian Chaco. Methods: Alpha-cypermethrin active ingredient (a.i.) captured onto filter papers fitted to sprayed wall surfaces, and in prepared spray tank solutions, were measured using an adapted Insecticide Quantification Kit (IQK™) validated against HPLC quantification methods. The data were analysed by mixed-effects negative binomial regression models to examine the delivered insecticide a.i. concentrations on filter papers in relation to the sprayed wall heights, spray coverage rates (surface area / spray time [m2/min]), and observed/expected spray rate ratios. Variations between health workers and householders' compliance to empty houses for IRS delivery were also evaluated. Sedimentation rates of alpha-cypermethrin a.i. post-mixing of prepared spray tanks were quantified in the laboratory. Results: Substantial variations were observed in the alpha-cypermethrin a.i. concentrations delivered; only 10.4% (50/480) of filter papers and 8.8% (5/57) of houses received the target concentration of 50 mg ± 20% a.i./m2. The delivered concentrations were not related to those in the matched spray tank solutions. The sedimentation of alpha-cypermethrin a.i. in the surface solution of prepared spray tanks was rapid post-mixing, resulting in a linear 3.3% loss of a.i. content per minute and 49% loss after 15 min. Only 7.5% (6/80) of houses were sprayed at the WHO recommended rate of 19 m2/min (± 10%), whereas 77.5% (62/80) were sprayed at a lower than expected rate. The median a.i. concentration delivered to houses was not significantly associated with the observed spray coverage rate. Householder compliance did not significantly influence either the spray coverage rates or the median alpha-cypermethrin a.i. concentrations delivered to houses. Conclusions: Suboptimal delivery of IRS is partially attributable to the insecticide physical characteristics and the need for revision of insecticide delivery methods, which includes training of IRS teams and community education to encourage compliance. The IQK™ is a necessary field-friendly tool to improve IRS quality and to facilitate health worker training and decision-making by Chagas disease vector control managers. [ABSTRACT FROM AUTHOR]

Copyright of Meteorologica is the property of Centro Argentino de Meteorologos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Boletín de la Sociedad Argentina de Botánica is the property of Sociedad Argentina de Botanica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent decades, global warming has intensified fires that have destroyed huge forested areas in various parts of the world. Argentina has not been exempted from this problem, nor has its province of Chaco. Therefore, this article attempts to give a geographical look at the issue of forest fires that occurred in nine departments in the east of this province during the period between 2015 and 2020. Through statistical analysis and georeferencing of information from different sources, the paper aims to identify the fire outbreaks that have been recorded in the study area described above and in that period of time, and characterize the current provincial management on the subject of fire risks. The production of cartography was made from the use of Qgis. In 2020, the region under analysis suffered a large number of fire outbreaks in rural areas that affected a little more than 60,000 hectares, destroying pastures, native and planted forests and, consequently, deteriorating soils, wildlife, and also damaging stubble cover and farmlands. [ABSTRACT FROM AUTHOR]

This paper analyzes and discusses the Law Nº 7446 named “Educación Pública de Gestión Comunitaria Bilingüe Intercultural Indígena" (Public Management Community Bilingual Intercultural Indigenous Education) approved in the Chaco province in 2014. Specifically reviews the discussions on the name of these Schools: Gestión Social (Social Management) and Gestión Comunitaria (Community Management). It also analyzes the involvement of the Community Council in the designation of the educational staff. The data used for this paper is: different versions of the Project Law, regional news press between 2010 and 2014, official speeches and some interviews with the people involved in this educational process (Union Educational Leaders and native teachers). This paper concludes thinking on the meanings of interculturality notion observed in the speeches of the social actors involved in Indigenous Education. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mundo de Antes is the property of Revista Mundo de Antes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper examines how the growing importance of natural gas production in the Bolivian Chaco has shaped the possibilities for lowland indigenous groups, such as the Weenhayek, to: a) recover ancestral lands; b) consolidate greater levels of self governance and autonomy; and c) and access flows of gas rents in order to sustain traditional ways of living. Through a focus on specific projects and processes of state-led Consultation and Participation, I explore how natural gas expansion has generated conflicts within Weenhayek society as well as between the Weenhayek, the Bolivian state and extractive industry enterprises. I argue that the tensions surrounding hydrocarbon expansion and processes of consultation must be understood in light of the particular economic calculations, territorial experiences and organizational dynamics of the Weenhayek in both historical and contemporary periods. These economic calculations are heavily marked by the logic of collection and the overriding importance of securing livelihoods - both in general but also from season to season. Tensions over hydrocarbons in Weenhayek territory must also be understood in a context in which government policies favor central political imperatives over the subnational projects of indigenous groups. [ABSTRACT FROM AUTHOR]

Objective: Failure to control domestic Triatoma infestans in the Chaco is attributed to vulnerable adobe construction, which provides vector refuges and diminishes insecticide contact. We conducted a pilot to test the impact of housing improvement plus indoor residual spraying (IRS) on house infestation and vector abundance in a rural community in the Bolivian Chaco. Methods: The intervention included three arms: housing improvement + IRS [HI], assisted IRS [AS] in which the team helped to clear the house pre‐IRS and routine IRS [RS]. HI used locally available materials, traditional construction techniques and community participation. Vector parameters were assessed by Timed Manual Capture for 2 person‐hours per house at baseline and medians of 114, 173, 314, 389 and 445 days post‐IRS‐1. A second IRS round was applied at a median of 314 days post‐IRS‐1. Results: Post‐intervention infestation indices and abundance fell in all three arms. The mean odds of infestation was 0.29 (95% CL 0.124, 0.684) in the HI relative to the RS arm. No difference was observed between AS and RS. Vector abundance was reduced by a mean 44% (24.8, 58.0) in HI compared to RS, with no difference between AS and RS. Median delivered insecticide concentrations per house were lower than the target of 50 mg/m2 in >90% of houses in all arms. Conclusion: Housing improvement using local materials and community participation is a promising strategy to improve IRS effectiveness in the Bolivian Chaco. A larger trial is needed to quantify the impact on reinfestation over time. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Conservation policies often promote land privatization to reduce incentives for deforestation. However, empirical evidence on the relationship between land‐tenure form and forest conservation outcomes is inconclusive. We combined key informant mapping and geospatial analyses to test the association between the area under tenure and the area deforested by extra‐local private and local nonprivate agents in the Argentine Dry Chaco over four decades (1976–2016). The study area is a typical commodity production frontier within a global deforestation hotspot. We found a strong spatial and temporal coupling between the area under tenure and the area deforested by extra‐local private agents from 1987 to 2006, when a 59% increase in the former was accompanied by a 508% increase in the latter. Local private agents maintained high levels of forest cover, similarly to local nonprivate agents. Our findings have implications for the adaptive design of the Forest Law in the Argentine Dry Chaco. [ABSTRACT FROM AUTHOR]

• Disturbance histories and climatic conditions accentuate forest structure and diversity. • Species composition differs between a preserved area and disturbed area. • Low forest structure is more frequent at disturbed sites. • Plant functional traits exhibited conservative and acquisitive strategies at the sampling sites. Over the last two decades, the Chaco region has experienced accelerated land-conversion processes that have developed into a mosaic of disturbances attributable to fires, forest logging, and livestock grazing in its native forests. In this paper, we describe the species composition and structure of two forests in semi-arid Argentine Chaco. Both forests have kept two different land uses in the last three decades: (a) a protected area (NR-Pizarro), and (b) an experimental area (ER-Inta) with land management practices. We analyse changes in species composition and plant functional traits as a response to disturbance history. We differentiate the disturbance history of the last 30 years in both sampling sites. To measure the plant communities, we used transects. We determined species, plant stem diameter, and height of 1315 woody plants >1 cm in diameter. Selected plant functional traits included: growth form, number of stems, spinescence, intensity of sprouts, and leaf texture. We registered 36 native woody species belonging to the Fabaceae and Capparaceae families. We found differences in the species composition of both sampling areas. Plant diameter and height averages decreased when comparing the protected area to the experimental area. Shrubby growth form, coriaceous leaves, absence of spines, and low sprouts were more frequent in the protected area. By contrast, in the experimental area, subshrubs, spines, and high sprouts prevailed. We reaffirmed the gradient of disturbances in both areas. A broader separation in plant functional traits occurred in the two sampling areas due to disturbance histories. [ABSTRACT FROM AUTHOR]

Copyright of Rodriguésia is the property of Revista Rodriguesia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tropical Grasslands / Forrajes Tropicales is the property of International Centre for Tropical Agriculture - CIAT and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tropical Grasslands / Forrajes Tropicales is the property of International Centre for Tropical Agriculture - CIAT and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Anthropogenic activity leading to forest structural and functional changes needs specific ecological indicators and monitoring techniques. Since decades, forest structure, composition, biomass, and functioning have been studied with ground-based forest inventories. Nowadays, satellites survey the earth, producing imagery at different spatial and temporal resolutions. However, measuring the ecological state of large extensions of forest is still challenging. To reconstruct the three-dimensional forest structure, the structure from motion (SfM) algorithm was applied to imagery taken by an unmanned aerial vehicle (UAV). Structural indicators from UAV-SfM products are then compared to forest inventory indicators of 64 circular plots of 1000 m2 in a subtropical dry forest. Our data indicate that the UAV-SfM indicators provide a valuable alternative for ground-based forest inventory' indicators of the upper canopy structure. Based on the correlation between ground-based measures and UAV-SfM derived indicators, we can state that the UAV-SfM technique provides reliable estimates of the mean and maximum height of the upper canopy. The performance of UAV-SfM techniques to characterize the undergrowth forest structure is low, as UAV-SfM indicators derived from the point cloud in the lower forest strata are not suited to provide correct estimates of the vegetation density in the lower strata. Besides structural information, UAV-SfM derived indicators, such as canopy cover, can provide relevant ecological information as the indicators are related to structural, functional, and/or compositional aspects, such as biomass or compositional dominance. Although UAV-SfM techniques cannot replace the wealth of data collected during ground-based forest inventories, its strength lies in the three-dimensional (3D) monitoring of the tree canopy at cm-scale resolution, and the versatility of the technique to provide multi-temporal datasets of the horizontal and vertical forest structure. [ABSTRACT FROM AUTHOR]